If there are 25 questions, each correct answer gives 2 marks, and each wrong answer deducts 0.5 marks, a student secures 37.5 marks. How many wrong answers did the student have?

None of these

Let x be the number of correct answers

Number of wrong answers = 25 - x

Total marks = 2x - 0.5(25 - x) = 37.5

Simplifying the equation, we get:

2x - 12.5 + 0.5x = 37.5

2.5x = 50

x = 20

So, the number of correct answers is 20, and the number of wrong answers is:

25 - 20 = 5